<!DOCTYPE html>
<html>

<head>
    <meta charset="UTF-8" />
    <title>更新时的一个问题</title>
    <script type="text/javascript" src="../js/vue.js"></script>
</head>

<body>
    <!-- 准备好一个容器-->
    <div id="root">
        <h2>人员列表</h2>
        <button @click="updateMei">更新马冬梅的信息</button>
        <ul>
            <li v-for="(p,index) of persons" :key="p.id">
                {{p.name}}-{{p.age}}-{{p.sex}}
            </li>
        </ul>
    </div>

    <script type="text/javascript">
        Vue.config.productionTip = false

        const vm = new Vue({
            el: '#root',
            data: {
                persons: [{
                    id: '001',
                    name: '马冬梅',
                    age: 30,
                    sex: '女'
                }, {
                    id: '002',
                    name: '周冬雨',
                    age: 31,
                    sex: '女'
                }, {
                    id: '003',
                    name: '周杰伦',
                    age: 18,
                    sex: '男'
                }, {
                    id: '004',
                    name: '温兆伦',
                    age: 19,
                    sex: '男'
                }]
            },
            methods: {
                updateMei() {
                    // this.persons[0].name = '马老师' //奏效
                    // this.persons[0].age = 50 //奏效
                    // this.persons[0].sex = '男' //奏效
                    // this.persons[0] = {id:'001',name:'马老师',age:50,sex:'男'} //不奏效
                    this.persons.splice(0, 1, {
                        id: '001',
                        name: '马老师',
                        age: 50,
                        sex: '男'
                    })
                }
            }
        })
    </script>

</html>